The man of true genius never lives before his time, he never undertakes impossibilities, and always embarks on his enterprise at the suitable place and period. Though he may catch a glimpse of the coming light as it gilds the mountain top long before it reaches the eyes of his contemporaries, and he may hazard a prediction as to the future, he acts with the present.
Joseph HenryThe general mental qualification necessary for scientific advancement is that which is usually denominated "common sense," though added to this, imagination, induction, and trained logic, either of common language or of mathematics, are important adjuncts.
Joseph Henry